// 设置cookie
function setCookie(key,value,time=3600){
  document.cookie=`${key}=${value};Max-Age=${time}`;
}
// 删除cookie 
function delCookie(key){
    document.cookie=`${key}=;Max-Age=-1`;
}
// 获取cookie
function getCookie(key){
    let str=document.cookie;
    // name=zhangan; age=20;  -->name?
    let arr=str.split("; ");
    // [name=zhangan,age=20];
    for(let i=0;i<arr.length;i++){
        let oneArr=arr[i].split("=");//[name,zhangsan]
        if(oneArr[0]==key){
            return oneArr[1];
            break;
        }
    }
}